Electrical means for producing sound.



0. STRITTER.

ELECTRICAL MEANS FOR PRODUGING SOUND.

APPLIOATIQN FILED Nov. 9, 1911.

Patented Dec. 16, 1913.`

To all 'whom t may concern narran sraans rafrnnr ernten.

erro sfrnrr'rnn, or scnnnnnne, unna BERLIN, enmaanmnsszervon ro am. ens. :um a enNnsr, rnnnrnson a rnnnenarnnn'wnnxn, or s cnnnnnmnnamw,

GERMANY.

EJECTRICAL MEANS FOR PRODUCIN'G SOUND.

Patentes nee. ie, reis.

applicati@ mea november e, 1911. serial No. ceases.

Be it known that I, Orno Smrr'rnn, a subject of the German Emperor. and residing at Schneberg, near Berlin, Germany, have invented certain new and useful Im rovements in Electrical Means for Pro ucing Sound, of which t-he following is a ,specification. Y

My invention relates generally to electrical devices for producing sound and, particularly, to electric horns, and important objects are to provide that a pure note of any desired pitch can be obtained in such .devices, and to keep the consumption of current as low as possible.

To these ends, I employ in my improved horn or the like an armature having an automatic interrupter, the arrangement being such that the armature causes the diaphragm to vibrate and permanently tensions the same by means of a regulatable spring. Owing to being thustensioned, when the diaphragm vibrates it is always connected' with'the armature and those rattling and hammering accessory noises are avoided which are produced when the connection be` tween the diaphragm and the armature is temporarily broken. By connecting the armature with the diaphragm solely by spring-pressure I obtain the additional advantage that the diaphragm can vibrate freely at right anlgles to its own plate, so that it is impossib e for the same to he distorted and bent. I preferably give the armature the form of a bell-crank lever in order to make the entire sound-producing device as compact as possible. I regulate the pitch by means of an adjustable interrupting device for the armature current.

An additional improvement in one form of my invention is the simultaneous employl `ment of the regulatable spring for tensioning the diaphragm as an adjustable interrupting spring. and providing this spring with a regulatable stop. Owing' to this arrangement I obtain various advantages. Firstly. Vat the moment when the spring pressure ceases, thus when the armature current is stopped, the coupling;` pressure between the armature and diaphragm also ceases; consequently, the diaphragm can swing back with great. force: so that'the note is a specially pure one. Further, without iniiuencing the duration of contact I can permanently tension the diaphragm to any desired extent. If the stop were not adju@- able there is nol doubt but that, with a highly tensioned contact spring, the interrupter contact would be shifted in such manner as to be broken when the armature moved a short. distance. The consequence of this would be that the vibrations of the diaphragm would be smaller which wouldundesirably influence the strength of thel note, as the permanent ten'sionof the diaphragm isincreased. JOwing to the adjustability of the stop I am, however, able, when the same is placed low down, to establish the previous duration of contact and with it the like kind of vibration. f

One illustrative embodiment of my invention and modifications thereof are represented by way of example in the accompanying drawing, v wherein 4.

Figure 1 is a vertical elevation, partly in section, showing the simplest form of my invention comprising a regulatable spring for producing the preliminary or permanent tension and a special interrupting device;

Figs. 2 and 3 are like views of modified forms in which the tensioning spring is simultaneously the interrupting spring; they armature in Fig. 2 is angular., while in Fig. 3 a pin or rod is provided between the armature and thediaphragm.

The device according to Fig. `1 substantially consistsof a sound-box 1 closed at one end by a diaphragxm 2 held between rings 3. On the rear of the sound-box and above the diaphragm as shown inthe drawing is mounted a plate or bridge 4 on which is secured the automatic interruptor.

This comprises an electromagnet 5, an armature 6 and the interrupter contact-piece?. The armature forms one arm of a two-armed lever which is fulcrumed at 13 and has a second arm 8. The latter arm has in the bottom of its free end a small recess 24. In thisrests a pin`23 mounted on an imtermediate member or abutment 9 carried by .the diaphragm 2. The armature is under the action oil a tension spring 25 mounted above the electromagnet on the lbase thereof. This spring is adjusted in such manner that the lever arm 8 engaging with the pin 23 tensions the diaphragm 2, whereby the diaphragm is bent downward. When the armature is released the 'contact piece 7 contacts with the contact piece 10 carried' by the arm 8. The contact piece 7 is on the interrupting spring 11 mounted' inthe support 26. rIhis sprmg can be adjusted by the screw 12 in such manner that the arm 8- bears firmly against thev intermediate abutment 9\ so 'thatl when the devicejy is in\ operation hammeringV movements between' the arm 8 and the intermediate abutment 9v or thediaphragm 2'cannot beproduced.

Any suitable means may be utilized for operatively connecting the lever arm 8 with the diaphragm 2 orltheintermediateabut-- ment 9.' "I he forni shown in tedrawing, however," is desirable in that ,the diaphragm may vibrate at rightangl'es toits own plane without being' bent or twisted owing to the 'arm'8 moving' in, an arc oa circle, this,

having heretofore frequently led"to rupture ofthe diaphragm at'its place of attachment.

In thev form according spring or'tensioning t e diapiragm is employed. 4The interrupting spring simultaneously serves this purpose. The interrupt#v ingispringfll 's adjusted bythe screw12 in such manner that it presses sufficiently *that accordingv to Fig. 2 only in that. the

electromagnet 5 is arranged on the plate 4 centrally'relatively to the diaphragm. The armature 6' of the`electromagnet is'connected with a pin 16 ,which imparts its move- 'ment to the diaphragm. Further, the break contact piece 10 is directly on the armature.

' In addition, the interrupting spring 11 and the stop`14 are arranged in separate supports '21 and' 22, respectively, each having a bar 18,19, respectively, for carrying the adjusting and regulatingscrews 15 and 12.

-Inorder to start working one of the devices according to Figs. 1 to 3 the interrupting springs 11, the contact pieces 7, 10, the armatures 8, 6` and the winding of the electromagnet 5 are connected in series, whereupon the ends of this circuit are connected to a source 'of current. The device theny 'The' armature 6 is attracted by the energizedelectromagnet 5 whereby the arm-8 depresses the Vdiaphragm 2 by means of the intermediate abutment 9 or the" pin 16. In consequence of the elasticity 'of the spring 11 or 25 the contact?, l()l is opened'. As the circuit is now broken the armature 6 i's released until the contact 7, 10' is closed again. This play of the armature l6 and the spring 11 or 25 is repeated in very rapid succession,

4`figoeneees to Fior. 2 no specialV gri..

whereby the diaphragm -2 isvibr'atedvery rapidly. In the forms according to Figs. 2 and 3 thel stroke` of thespring 11 is 'limited by the stop 14. If it is wished to produce a khigher note the screw 12 must bescrewed farther in,whereby the diaphragm is more highly tensioned in consequence of the presstop 14 must be adjusted by the screw 15 in such'` manner that the motion Vof the c spring 11 is checked at the proper moment.`

Consequently, the adj ustablestop 14 ,enables ruptings ring 1 1 611 the movin mechanism, between t e armatureand the iaphragmis land the winding of the electromagnetv are tacts 27 and 28.

I claim 1. In electrical means. .for producing sound, the combination with a. diaphragm,

with said electromagnet. and operatively engaging said diaphragm, a contact piece carried by' said-.armature',ad a tensioned'interrupting spring carrying a cont-act 'piece normally ,depressing said first mentioned the form of a bell-crank lever, an abutment carried /by the diaphragm supporting one arm of the armatureatensionspring at tached to the other armof the armature and tendingv to depress the former arm', the

piece 'normally coacting with the former contact piece, the said armature being electrically connected in series with the winding of the electromagnet.

3. In electrical sound, the combinationwith 'a diaphragm, of an electromagnet, an armature coacting with said electromagnet and operatively engaging said diaphragm, a contact piece carried by said armature, and a regulatably tensioned interrupting spring carrying a contact piece normally depressing said first mentioned contact piece and thereby tension- 1ng the diaphragm, the said armature beingy electrically connected in series with the winding of the electromagnet.

4. In electrical means for producing sound, the combination with a diaphragm, of an electromagnet having an armaturel in. the form of a bell-crank lever, an abutment carried by the diaphragm supporting one arm of the amature, a regulatable tension closed by closing the hand-operated; con# former arm carrying a contact piece, and ,an lnterruptmg spring carrylng a contact means for producing sure' ofthe spring `being increased. "Ihe the make and break contactl?, 10 to beregullated.even when the pressure 4of the nite'r,

varied. The circuits between the arinatures'l of an electromagnet, an armature counting spring attached to the other arm of the armature and tending to depress the former arm, the vformer arm carrying a contact iece, and a regulatably tensioned interruptlng spring carrying a contact piece normally coacting with the former Contact piece, the said armature being electrically connected in series with the Winding of the electromagnet.

5. In electrical means for producing sound, the combination with a diaphragm, of an abutment carried by said diaphragm, an electromagnet, an armature having an arm resting on said abutment, a contact iece carried by said arm, and a tensioned interru tin spring carrying a contact piece normal y epressing said first mentioned contact piece and thereby tensioning the diaphragm, the said armature being electrically connected in series with the Winding of the electromagnet.

said spring for coacting with said first mentioned contact, said spring normally acting upon said armature, through said contacts, to tension said diaphragm, and means for adjusting the tension of said spring, substantially as and for the purpose set forth.

7. In electrical means for producing sound, the combination of a diaphragm, an electromagnet disposed with its core substantially parallel to the plane of said diaphragm, a pivotally mounted armature having one end extending over said diaphragm and adapted to move in a plane substantially perpendicular lto the plane of said diaphragm, said arm operatively engaging said diaphragm, a contact carried by said arm of said armature, an interrupting spring, a contact carried by said spring for coaction with said rst mentioned contact, and means for tensioning said spring to normally depress said diaphra substantially as and for the purpose set orth.

In testimony whereof I ailix my signature in presence of two Witnesses.

OTTO STRITTER.

Witnesses:

HENRY HASPER,

WOLDEMAR HAUPT. 

